Microchip Technology 93LC46A-I/MS

Overview

93LC46A-I/MS from Microchip Technology Inc. is a 1 Kbit (128 × 8-bit) low-voltage serial EEPROM with Microwire-compatible 3-wire interface, operating from 2.5 V to 5.5 V, rated for industrial temperature range (−40°C to +85°C), and packaged in an 8-lead MSOP. It features self-timed erase/write cycles, automatic ERAL before WRAL, and Ready/Busy status signaling via DO pin - used for configuration storage in microcontroller-based embedded systems.

For engineers reviewing the 93LC46A-I/MS datasheet, 93LC46A-I/MS pinout, 93LC46A-I/MS application, or 93LC46A-I/MS equivalent, key selection considerations include its fixed 8-bit organization (no ORG pin), 3 MHz max clock frequency at VCC ≥ 4.5 V, 6 ms typical write cycle time, RoHS-compliant Pb-free MSOP package, and support for sequential read and power-on data protection.

Technical Context

The 93LC46A-I/MS implements a synchronous serial Microwire interface with CS, CLK, and DI/DO pins - no ORG pin present, confirming fixed 8-bit word organization. Its internal architecture includes auto-erase-before-write logic, integrated power-on reset detection (VPOR = 1.5 V), and hardware-level write protection via EWEN/EWDS commands.

It supports full memory erase (ERAL) and write-all (WRAL) operations requiring VCC ≥ 4.5 V, and provides device status via DO pin polling during programming. All timing parameters - including TCSL (250 ns min), TPD (≤400 ns), and TWC (6 ms) - are specified across −40°C to +85°C and 2.5 V–5.5 V supply range.

Key Specifications

Pinout & Package

8-lead MSOP (Micro Small Outline Package), 3.0 mm × 3.0 mm body, 0.65 mm pitch, exposed pad optional (VSS or floating). Pin 1 marked by laser dot; pin 1 ID corner defined per JEDEC MO-187.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar serial EEPROM applications.

Compared with 93LC46B-I/MS, the 93LC46A-I/MS avoids 16-bit address translation complexity; compared with AT25010B-MAHL-T, it delivers deterministic timing via DO status signaling and requires one fewer PCB trace - critical for space-constrained motor control modules.

Availability

93LC46A-I/MS is available at Aetrix Electronics and suitable for motor control configuration storage, smart sensor calibration data, and medical device setup parameters requiring stable component supply across extended production lifecycles.

Supply support for 93LC46A-I/MS includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Microchip Technology Inc. is a leading provider of microcontrollers, analog components, and memory solutions, headquartered in Chandler, Arizona, with global manufacturing and support infrastructure.

The 93LC46A-I/MS belongs to Microchip's legacy 93XX serial EEPROM family, designed specifically for cost-sensitive, low-power embedded systems requiring reliable nonvolatile storage with minimal pin count and robust power-supply immunity.

FAQ

What is the function of the NC pin on the 93LC46A-I/MS?

The NC (No Connection) pin on the 93LC46A-I/MS is Pin 7 in the 8-lead MSOP package and has no internal connection. It must remain electrically floating or be tied to VSS per PCB layout guidelines - it cannot be used for strapping, debugging, or signal routing. This pin exists due to package compatibility with the 'C' variant (which uses ORG), but is unused in the 'A' version like the 93LC46A-I/MS.

Does the 93LC46A-I/MS require an external pull-up resistor on the DO line?

No, the 93LC46A-I/MS does not require an external pull-up on DO. The DO pin actively drives high/low during read or Ready/Busy status reporting and enters High-Z when deselected (CS low) or idle. A pull-up is unnecessary and may interfere with valid low-level status signaling. External termination is only needed if DI and DO are shorted - then a 10 kΩ series resistor is recommended to prevent bus conflict.

Can the 93LC46A-I/MS operate reliably at 2.5 V supply voltage?

Yes, the 93LC46A-I/MS is fully specified down to 2.5 V: AC parameters (e.g., TPD ≤ 400 ns, FCLK ≥ 1 MHz), DC characteristics (VIH1 ≥ 2.0 V), and functional operation (ERAL/WRAL disabled below 4.5 V, but READ/WRITE remain active) are guaranteed across 2.5–5.5 V. This makes it suitable for battery-powered or low-voltage microcontroller systems.

How does the 93LC46A-I/MS handle power loss during a write cycle?

The 93LC46A-I/MS incorporates hardware power-loss protection: its internal voltage detector (VPOR = 1.5 V) disables all write operations when VCC drops below this threshold. Combined with automatic erase-before-write and EWDS default-on-reset behavior, this ensures no partial or corrupted writes occur during brown-out events - preserving data integrity without host firmware intervention.

Is the 93LC46A-I/MS pin-compatible with the 93AA46A-I/MS?

Yes, the 93LC46A-I/MS and 93AA46A-I/MS share identical 8-lead MSOP packaging, pinout, and 128 × 8-bit organization. However, they differ in VCC range (93AA46A: 1.8–5.5 V; 93LC46A: 2.5–5.5 V) and AC timing (93AA46A supports 3 MHz down to 1.8 V). For designs operating ≥2.5 V, they are functionally interchangeable with no PCB changes required.